<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    
</body>
<script>

    //
    var arr = [3,2,5,1,9,15];//sort()默认只能对1-9之间的数字进行排序
    var arr1 = arr.sort(function(a,b){
        return a-b;
    });
    console.log(arr1);
    console.log(arr1.reverse());
</script>
</html>